US3469483A

US3469483A - Plate side trimming shear

Info

Publication number: US3469483A
Authority: US
Inventors: David Hobson; Derek Hattersley
Original assignee: Davy Loewy Ltd
Current assignee: Davy Loewy Ltd
Priority date: 1965-10-06
Filing date: 1966-10-04
Publication date: 1969-09-30
Anticipated expiration: 1986-09-30
Also published as: DE1552593A1; GB1131496A

Description

Sept. 30, 1969 D. HOBSON ETAL 3,469,483

PLATE SIDE TRIMMING SHEAR Filed Oct. 4, 1966 4 Sheets-Sheet 1 INVENTORS I DAVID HOBSON a DEREK HATTERSLEY b 6% :4 9 Q THEIRATTORNEY Sept. 30, 1969 p. HOBSON ETAL 3,469,483

' PLATE SIDE 'rnmmms smzma Filed Oct. 4, 1966 4 Sheets-Sheet 2 VHF-J F/GiZ.

INVENTORS DAVID HOBSON & BY DEREK HATTERSLEY TH i ATTORNEY Sept. 30, 1969 o. HOBSON ETAL 3,469,483

PLATE SIDE TRIMMING SHEAR Filed Oct. 4, 1966 4 Sheets-Sheet 5 INVENTORS DAVID HOBSON & BY DEREK HATTERSLEY T EIR ATTORNEY Sept. 30,- 1969 ogsofl ETAL 3,469,483

PLATE sum TRIMMING snmry Filed Oct. 4, 1966 4 Sheets-Sheet 4.

INVENTORS DA/ID HOBSON & BY DEREK HATTERS LEY United States Patent U.S. Cl. 83-216 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a shear of the type used to side trim metallic plate. The shear comprises a pair of blade holders, each having a cooperative blade. The upper blade holder is reciprocated towards and away from the other blade holder, which is stationarily mounted. The upper blade holder is carried in a pivotal guide to which there is connected a backing-off device. The backing-01f device is made up of a first link having one end pivotally connected to the guide and the other end to a second link, which is pivotally carried by the shear frame. A connecting rod is also provided, which is connected to the links and the main drive of the shear.

This invention relates to opposed side trim shears. With such shears, where the opposite sides of a plate are to be cut simultaneously, it is necessary to draw the blades of the shears away from the cut edges of the plate on the return stroke of the shear. This is referred to as backing-01f of the blades.

The present invention provides a shear having a pair of blade holders adapted to carry a pair of cooperating blades, drive means for reciprocating a first of the blade holders towards and away from the other blade holder in a pivotally mounted guide to effect a shear, and a backing-01f device, the backing-off device comprising a substantially horizontal linkage pivotally coupled between the guide and a part of the shear frame and having an intermediate pivot point, and mechanical means for pivoting the linkage at its intermediate point at the end of the cutting stroke. The horizontal linkage is held in a fixed position during the cutting stroke of the shear. By this means, during the cutting stroke the movable blade travels in a perfectly straight vertical line, and when the linkage pivots at the end of the cutting stroke the withdrawal away from he plate is rapid.

Preferably the backing-off device comprises a linkage including a first substantially horizontal link having one end pivotally coupled to the guide and the other end pivotally coupled to one end of a second substantially horizontal link which has its other end pivotally coupled to the shear frame, and means coupled between the blade drive and the pivot between the links, movable relative to the links during the cutting stroke and arranged to engage the links at the end of the cutting stroke to displace the centre pivot point.

Preferably the pivotal coupling between the end of the linkage and the shear mounting is adjustable in order to adjust the separation of the blades of the shear. In one form the end of the linkage is mounted eccentrically on a shaft and the shaft is arranged to be driven automatically by a motor to assume a position corresponding to a predetermined blade separation.

Material to be cut is preferably fed to the pair of opposed side shears on an entry roller table and removed from the shears on an exit roll table. Another aspect of the invention provides that the entry and exit roller tables are line shaft driven, the entry table having an automatic control for the drive to meter material into the shear.

The exit roller table has a separate control motor, but the entry and exit roller tables can be connected together during cutting.

One embodiment of opposed side trim shear arrangement, in accordance with the invention, will now be described, by way of example only, with reference to the accompanying drawings of which:

FIGURE 1 is a plan view of an opposed side trim shear arrangement,

hFIGURE 2 is a front view partly in section of one s ear,

FIGURE 3 is a side view of the shear in FIGURE 2,

FIGURE 4 is a sectional view on the line IV-IV of FIGURE 2.

The shear arrangement shown in FIGURE 1 includes two opposed side trim shears, one 12 being a fixed shear and the other 13 being arranged to move towards or away from the fixed shear to accommodate different widths of plate. An exit roll table 14 has a plurality of rollers 15 driven by a line shaft drive arrangement from a common motor 1-6. A moving longitudinal side guide 17 is driven through shafts 18 and gear boxes 20 by a motor 19. The movable shear 13 is also driven by motor 19, and since the other end of the side guide 17 is fixed to the shaft 13, the side guide 17 always remains parallel to a fixed side guide 17A at the other side of table 14.

An entry roller table 21 comprises a plurality of rollers 22 each driven through a line shaft 23 from a common motor 24. Motors 16 and 24 may be connected as shown. A longitudinal travelling magnet 25 is driven from a motor 24A, which when desired may be synchronised with motor 24 through shafts 26, this then synchronises the travelling magnet with the entry roller table. Cross travel magnets 27 are employed on the entry roller table to line up the plate prior to shearing. A centre support table 28 is provided bridging the entry and exit roller tables, this table also being driven by the motor 19 and arranged always to be midway between the shears 12 and 13. A scrap conveyor 30 is provided for removing the scrap from beneath the shears. Separate automatic controls are provided for the motors 16 and 24 so that the entry and exit tables may be driven independently. The moving shear 13, shown in detail in FIGURES 2, 3, and 4, comprises a main shear frame 31 mounted on slides 32 fastened to beams 33 for sliding movement towards and away from the fixed shear. The shear is driven from the motor 19 through screws 33A. The frame 31 carries a fixed lower blade 34 and an upper blade 35 carried in a blade holder 36 mounted in a guide 37 for vertical sliding movement relative thereto. The guide 37 has an integral pin 38 either side carried in the frame 31 so that the guide carrying the blade holder and blade can pivot about the horizontal axis 40 of the pin, parallel to the movement of material through the shear. Gags 41 are mounted on the frame to clamp material to be cut between the gags and the lower blade 34.

A motor 42 is mounted on the frame 31 and connected through a brake and coupling 43 to a worm 44 engaging a worm wheel 45 keyed on a crank shaft 46 rotatably mounted in bearings 47 in the frame 31 for rotation about its horizontal axis 48 parallel to the axis 40. The centre part 50 of the shaft 46 has its axis 51 displaced from the axis of rotation of the shaft and carries on bearings 52a double connecting rod 53 integral at its lower end 54. The lower end 54 is seated in a pitman bearing 55 at the top of the blade holder 36, and is held in the seating 55 by a tie 56. It will be seen that rotation of the shaft 46 reciprocates the blade holder 36 carrying the upper blade 35 up and down by means of the eccentrically mounted connecting rod 53, the blade holder 36 sliding in the guide 37. A balance cylinder 56A is used to take the weight of the blade holder 36.

On each side of the shear is located a mechanical backing-off device in the form of a toggle mechanism, only one of which will be described, best seen in FIGURE 3. A horizontal link 57 has one end 58 connected to the guide 37 for pivotal movement about a horizontal axis 60, and has its other end 61 pivotally mounted on a pin 62 having a horizontal axis 63; a second horizontal link 64 has one end 65 pivotally carried on the pin 62 and its other end 66 pivotally mounted on a pin 67 having a horizontal axis 68, the pin 67 being an eccentric on the end of a shaft mounted for rotation in the frame 31. By shifting the position of axis 68, the horizontal separation of

blades

34 and 35 can be adjusted. A motor is coupled to the shaft carrying the pin 67 to automatically fit the eccentric to a position corresponding to a predetermined blade separation. Also coupled to the pin 62 is a toggle 70 carried on the piston rod 71 of a cylinder 72 pivotally mounted on a pin 73 fixed to the frame 31. The piston and cylinder assembly 72 is pressurised to apply a downward bias to the links 57 and 64, maintaining them in their substantially horizontal position by means of a stop 69 under the toggle 70. The piston rod 71 passes through a clearance hole in the stop 69, which is fixed to the frame 31. A link 74 has its upper end 75 pivotally mounted on a pin 76 eccentrically carried on the end of the crank shaft 46, and its lower end 77 is formed with a slot 78 in which the pin 62 is received. The slot 78 is arranged so that during the downward stroke of the blade the link 74 moves in such a way that no force is exerted on the pin 62 and therefore there is no movement of the links 57 and 64. At the end of the cutting stroke the bottom end 80 of the slot 78 contacts the bottom of the pin 62. On further rotation of the shaft 46, the link 74 lifts the pin 62 against the pressure of the cylinder 72, thereby causing the links 57 and 64 to pivot. Since the end 66 of link 64 is fixed, the end 58 of link 57 is drawn towards the shear, thus pulling the lower end of the guide towards the frame 31. Since the guide 37 is pivoted at axis 40, the guide 37 rotates, and the blade 35 carried in the blade holder 36 is drawn away from the sheared edge; this backing-off of the blade away from the sheared edge being extremely rapid.

On further rotation of the shaft 46, the pin 62 reaches the top of its lift,-and thereafter the pin 62 is returned to its original position by the cylinder 72 being controlled by link 74. When the toggle 70 is lowered on to the stop 69, the links 57 and 64 are again substantially straight, and the cutting stroke then begins.

A heel blade 81 cuts each sheared piece of plate off, and allows the scrap to fall onto the conveyor 30.

In accordance with the provisions of the patent statutes, we have explained the principle and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof. However, we desire to have it understod that within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

What is claimed is:

1. A shear including a frame and a pair of blade holders adapted to carry a pair of cooperating blades,

a guide for receiving a first blade holder in a manner to permit relative movement therebetween,

means supported by said frame for carrying said guide in a manner to restrict movement of the guide to only a pivotal movement and in a direction towards and away from the sheared edge of the material,

drive means for reciprocating said first blade holder towards and away from the other blade holder to effect a shear,

a backing-off device comprising a substantial linkage pivotally coupled between the guide and a part of the shear frame and having an intermediate pivot point, and

mechanical means for pivoting the linkage at its intermediate point at the end of the shearing stroke.

2. A shear having a frame which receives a pair of blade holders adapted to carry a pair of cooperating blades;

a drive means for reciprocating a first of the blade holder towards and away from the other blade holder in a pivotally mounted guide to effect a shear;

a backing-off device comprising a substantially horizontal linkage pivotally coupled between the guide and a part of the shear frame and having an intermediate pivot point; and

mechanical means including a further link coupled between the linkage and the drive means and arranged to move freely relative to the linkage during the cutting stroke and to engage the linkage in the end of the cutting stroke to displace the intermediate pivot point.

3. A shear according to claim 2 in which the further link is connected to the linkage by a pin and slot coupling.

4. A shear according to claim 2 in which the drive means includes a shaft to which the first blade holder is eccentrically connected, and the further link is also eccentrically connected to the shaft.

5. A shear according claim 2 including retaining means for holding the linkage horizontal during the cutting stroke.

6. A shear according to claim 5 in which the retaining means are hydraulic and act, in the opposite direction to the action of the mechanical means on the linkage to urge the intermediate point of the linkage against astop.

7. A shear according to claim 2 in which the linkage is arranged to maintain a blade in the first blade holder substantially vertical during the whole cutting stroke.

8. A shear according to claim 2 in which the pivotal coupling between the linkage and the part of the shear frame is adjustable to vary the horizontal separation of the shear blades.

9. A shear according to claim 8 in which the end of the linkage coupled to the shear frame part is eccentrically mounted on a shaft arranged to be driven automatically to assume a position corresponding to a predetermined blade separation.

10. A pair of side trimming shears according to claim 2 in combination with line shaft driven entry and exit roller tables, the entry table having an automatic control for the drive to meter material into the shear.

References Cited UNITED STATES PATENTS 3,154,988 11/1964 Gries 83-558 X 3,246,552 4/1966 Sieger 83-556 X 3,263,546 8/1966 Musly et a] 83556 WILLIAM S. LAWSON, Primary Examiner U.S. Cl. X.R. 83-556